Instructions on how to Repack a Precolumn

To repack a precolumn, you will need a few items.

Packing material (word of forewarning: work in a well ventilated environment to prevent the inhalation of the packing material)

A syringe connected to a length of PEEK tubing and a fitting to connect it all to the precolumn

A filter push tool to remove old filters

Filter(s)

Precolumn(s)

wrenches to open and close the precolumns (adjustable wrenches are ideal)

2 extra syringes

100 uL pipette and tips

HPLC grade MeOH

HPLC grade water

1) cut off the end of a pipette tip to allow for more easier pickup of the packing material.  (optional)

2) add a small amount of MeOH to the packing material to make a slurry.  Adding too much or too little will make the packing material slurry either to thin or thick, which makes it harder to repack the precolumn.

3) If your precolumn is full of packing material, continue on this step.  If you are repacking an empty precolumn, proceed to step 6.  Using 2 wrenches, unscrew the 2 parts of the precolumn.  We recommend grabbing the precolumn with the wrenches at the main body (the part with the filter) and at the small hex fitting.  

4) remove the used filter by screwing the filter removal tool into the inlet of the precolumn.  If some packing material is left on this part of the precolumn, sonicate it in milli-Q water and wipe with a kimwipe until it is clean.

5) remove the old packing material by screwing the syringe/PEEK tubing assembly to the outlet of the precolumn.  With the syringe, push a small amount of methanol through it until the packing material is ejected.  If some small amount of packing material remains inside the precolumn, you can remove it in the same way as stated in step 4.  

6) Now that the two parts are clean, insert the filter into place.  Adding a small amount of methanol to the inside of the precolumn will make it easier to set the filter in place.  Take care to not damage the filter.

7) Connect the syringe/PEEK tubing assembly to the outlet of the precolumn using the fitting.  Aspirate a volume of the packing material slurry and add it to the hole.  When the precolumn fills with methanol and packing material, pull on the syringe to remove some methanol from the packing material.  Repeat this until you have the packing material make a small mound above the lip of the hole.  

8) (Optional) To check for any air gaps or imperfections, keep the tubing and syringe assembly together, and lightly push on the syringe.  The packing material will be pushed above the lip and you can check for mistakes there.  If you notice that it is packed badly (e.g. gaps, hole is not full) go back to step 3 to redo the repacking.

9) Now that the two parts of the precolumn are prepared, screw the two parts back together by hand until hand tight.  Make sure to not spill any packing material or let the filter fall out.  Once hand tight, use two wrenches to tightly screw the two parts together using the recommended positioning in step 3.  

10) attach the syringe/tubing assembly to the inlet of the precolumn and fill the syringe with ~2 mL MeOH.  Push the MeOH through the precolumn to wash it.  Perform this step twice.  This waste from this step can be drained into a waste container.  Careful: pushing the MeOH through the precolumn creates a lot of pressure, and the syringe can disconnect from the fitting it is attached to, so please be careful when performing this step.

11) Repeat step 10 but with milli-Q water.

12) cap the ends off with fittings to prevent the packing material from drying out.